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Incan metalwork

...of the Quimbaya, whose skill in creating polished metal flasks is remarkable. Notable also is Sinú casting, which could execute works weighing several pounds. In Ecuador the goldwork found at
La Tolita is legendary and shows a skill in casting and overlay that did not seem to exist elsewhere in the region. In Peru most surviving goldwork was created by the Chimú and Nazca peoples....

...unique; they are known in sufficient quantity to prove the existence of a longtime craft. Literally hundreds of thousands of tiny gold beads, each cast individually, have been found in the sands of
La Tolita; and others, slightly larger, with granulated surfaces indicating the mastery of a complex casting process, have also been recovered. The technique of inlaying had also been mastered, and...